Outline

Objective: The treatment of tumors near motor areas of the brain remains a surgical challenge. In most cases surgical aim is a total resection, however, preservation of neurological function remains the main goal. Therefore, several tools to map and monitor the motor tract have been implemented. The present study aims to elucidate the utility of DTI motor fiber tracking in the surgical treatment of motor eloquent tumors.

Methods: The departmental database was screened for patients fulfilling the inclusion criteria: i) surgery for intracranial tumors close to the motor tract, ii) intraoperative use of neuronavigation including fiber tracking, iii) intraoperative MEP monitoring. Preoperative MRI-scans were re-evaluated by 3 tumor surgeons concerning tumor location in relation to the motor tract, resectability and the best approach. These informations was gathered from MRI, initially without fiber tract information and afterwards including fiber tract information. Furthermore, we inserted preoperative fiber tracts in postoperative MRI scans to examine the relationship of the resection cavity to previous fiber tract information. Finally, patients' files were screened for pre- and postoperative neurostatus, and any influence of fibertracking data on the intraoperative resection strategy. The electrophysiological recordings were reviewed for intraoperative changes of potentials.

Results: Nineteen patients were identified according to the above inclusion criteria for the time period between May 2007 and April 2008. The determination of tumor localization in relation to the motor tract and the determination of theoretical resectability were not changed by the fiber tracking information in any of the cases by all 3 surgeons. In a single case, 2 of the 3 surgeons would have changed their surgical approach to the tumor after addition of the fiber tracking data. In all cases fiber tracking did not change the intraoperative strategy, i.e. resection was not modifed. However, MEP monitoring led to changes in surgical strategy in 2 cases.

Conclusions: In the present series, DTI fiber tracking did not influence the surgical planning or the extent of the resection. However, DTI fiber tracking is still used at our institution since it is easily acquired and could potentially have an impact on planning and resection in a larger series of patients. Furthermore, more experience using the technique has to be gained and it needs to be technically optimized to expand its benefit.